Has the Bottom Fallen Out of the Broadcast TV Ratings?

The latest batch of broadcast TV's currency data has been crunched, and while a handful of shows are doing their bit in the war against audience erosion, the Big Four networks's share of sellable ratings points continues to shrink at an alarming clip.

According to Nielsen, C3 ratings last month dropped 16 percent versus the year-ago period, as ABC, CBS, NBC and Fox combined for an average primetime draw of just 2.07 million adults age 18-49, down from the 2.47 million members of the demo that watched the ads in November 2016. And while the nets faced some tough year-to-year comps -- Fox was coming off a record-setting World Series, and results were somewhat overshadowed by last November's election -- this also marked the seventh month in which C3 ratings fell by double-digit percentages.

Developed as a compromise measure back in 2007, C3 blends a very rough estimate of average commercial ratings with three days of time-shifted viewing; as such, it offers networks, buyers and advertisers the best approximation of actual ad deliveries. Networks began negotiating against C7 deliveries five years after the original currency was adopted.

As Ad Age has taken pains to point out elsewhere, the three additional days of viewing generally don't help boost commercial impressions when compared to the vanilla live-same-day deliveries. Per the C3 data, the Big Four in November averaged a 1.6 rating in the 18-49 demographic, which marked an improvement of one-tenth of a ratings point when juxtaposed with the 1.5 rating they eked out during the same period in live-same-day.

This year the Nielsen calendar coincided with Weeks 6 through 9 of the 2017-18 broadcast season, a period that began on Oct. 30 and ended on Nov. 26. Two World Series games were played in November as it was defined by Nielsen; Fox's coverage of Games 6 and 7 of the Astros-Dodgers showdown averaged a 7.1 in the demo, or 9.14 million adults 18-49, down 26 percent from the final two frames of the Cubs-Indians classic, which drew a 9.6, or 12.3 million members of Fox's dollar demo.

As a result, Fox experienced the greatest year-to-year setback, plummeting 31 percent from an average draw of 3.29 million adults 18-49 in November 2016 to 2.27 million last month. When expressed in standard ratings nomenclature, Fox dropped from a 2.6 to a 1.8 in C3.

Top-rated NBC, which was more or less stabilized by its lineup of "Sunday Night Football," "This Is Us" and "The Voice," declined 11 percent to 2.88 million advertiser-coveted viewers (good for a 2.2 rating), while CBS fell 15 percent to 1.59 million, inching out ABC, which in averaging 1.58 million adults 18-49 over the course of the month, dropped 13 percent.

Fox in November was the only network that saw a discernible lift from live-same-day to C3, adding four-tenths of a point in the three-day currency. NBC, which extracts most of its gross ratings points from its live NFL programming and broadcast's biggest water-cooler show ("This Is Us"), squeezed out an extra tenth upon conversion from live-same-day to C3, while CBS and ABC were effectively unchanged.

Season-to-date, ABC's "The Good Doctor" continues to show the greatest improvement from live-same-day (the freshman series is averaging a 1.9 in the 18-49 demo) to C3 (2.5), and the freshman drama gains even more ground when the C7 currency is factored into the equation. According to Nielsen, "The Good Doctor" is now averaging a 2.8 rating in C7, or around 3.6 million commercial impressions among adults 18-49, an improvement of 47 percent compared to its original live-same averages.

Cable TV also took a hit in November, with ad-supported networks falling 11 percent in C3 compared to the year-ago period. Predictably, the network group that includes Fox News Channel took the biggest hit when compared with last November's election-inflated results, dropping 24 percent in C3, while the ongoing exodus of "Walking Dead" viewers squeezed AMC's monthly C3 ratings by 18 percent.

Through the Nov. 26 episode of "The Walking Dead," the eighth season is averaging a 3.9 in C3, or around 5 million adults 18-49. And while rival network exec would more or less surrender their eye teeth for those sort of demo deliveries, that also marks a vertiginous 30 percent drop-off compared to the year-ago 5.6 the show averaged in C3.